%%
%% The LaTeX Companion, 3ed
%%
%% Example 8-4-3 on page I-615 in "tcolorbox --- The basic usage".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{159.0pt}
%
\AddToHook{begindocument/end}{\tcbset{colback=blue!10, colframe=blue}}
%StartShownPreambleCommands
\usepackage{tcolorbox}
\tcbset{colback=blue!10!white, colframe=blue}
%StopShownPreambleCommands

\begin{document}
\begin{tcolorbox}[title=A box title]
 Default options are better defined using
 \verb=\tcbset{...}= for a uniform appearance.
\end{tcolorbox}
\end{document}
